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The chemical compositions of Earth's core and mantle provide insight into the processes that led to their formation. N-body simulations, on the other hand, generally do not contain chemical information, and seek to only reproduce the masses and orbits of the terrestrial planets. These simulations can be grouped into four potentially viable scenarios of Solar System formation (Classical, Annulus, Grand Tack, and Early Instability) for which we compile a total of 433 N-body simulations. We relate the outputs of these simulations to the chemistry of Earth's core and mantle using a melt-scaling law combined with a multi-stage model of core formation. We find the compositions of Earth analogs to be largely governed by the fraction of equilibrating embryo cores and the initial embryo masses in N-body simulations. Simulation type may be important when considering magma ocean lifetimes, where Grand Tack simulations have the largest amounts of material accreted after the last giant impact. However, we cannot rule out any accretion scenarios or initial embryo masses due to the sensitivity of Earth's mantle composition to different parameters and the stochastic nature of N-body simulations. Comparing the last embryo impacts experienced by Earth analogs to specific Moon-forming scenarios, we find the characteristics of the Moon-forming impact are dependent on the initial conditions in N-body simulations where larger initial embryo masses promote larger and slower Moon-forming impactors. Mars-sized initial embryos are most consistent with the canonical hit-and-run scenario onto a solid mantle. Our results suggest that constraining the fraction of equilibrating impactor core and the initial embryo masses in N-body simulations could be significant for understanding both Earth's accretion history and characteristics of the Moon-forming impact.

At the interface of Earth's upper and lower mantle, the post-spinel transition boundary controls the dynamics and morphologies of downwelling slabs and upwelling plumes, and its Clapeyron slope is hence one of the most important constraints on mantle convection. In this study, we reported a new in situ experimental dataset on phase stability in Mg$_{2}$SiO$_{4}$ at mantle transition zone pressures from laser-heated diamond anvil cell experiments, along with a compilation of corrected in situ experimental datasets from the literature. We presented a machine learning framework for high-pressure phase diagram determination and focused on its application to constrain the location and Clapeyron slope of the post-spinel transition: ringwoodite $\leftrightarrow$ bridgmanite + periclase. We found that the post-spinel boundary is nonlinear and its Clapeyron slope varies locally from $-2.3_{-1.4}^{+0.6}$ MPa/K at 1900 K, to $-1.0_{-1.7}^{+1.3}$ MPa/K at 1700 K, and to $0.0_{-2.0}^{+1.7}$ MPa/K at 1500 K. We applied the temperature-dependent post-spinel Clapeyron slope to estimate its lateral variation across the "660-km" seismic discontinuity in subducting slabs and hotspot-associated plumes worldwide, as well as the ambient mantle. We found that, in the present-day mantle, the average post spinel Clapeyron slope in the plumes is three times more negative than that in slabs, and we then discussed the effects of a nonlinear post-spinel transition on the dynamics of Earth's mantle., Comment: 42 pages, 6500 words and 5 figures in the main text, and 1 supplement with 6 texts, 5 figures, and 6 tables

Progressive astronomical characterization of planet-forming disks and rocky exoplanets highlight the need for increasing interdisciplinary efforts to understand the birth and life cycle of terrestrial worlds in a unified picture. Here, we review major geophysical and geochemical processes that shape the evolution of rocky planets and their precursor planetesimals during planetary formation and early evolution, and how these map onto the astrophysical timeline and varying accretion environments of planetary growth. The evolution of the coupled core-mantle-atmosphere system of growing protoplanets diverges in thermal, compositional, and structural states to first order, and ultimately shapes key planetary characteristics that can discern planets harboring clement surface conditions from those that do not. Astronomical campaigns seeking to investigate rocky exoplanets will require significant advances in laboratory characterization of planetary materials and time- and spatially-resolved theoretical models of planetary evolution, to extend planetary science beyond the Solar System and constrain the origins and frequency of habitable worlds like our own., Comment: 37 pages, 10 figures; under review for publication as a chapter in Protostars and Planets VII, University of Arizona Press; comments welcome; figures available at https://osf.io/rcjt7

The Earth and Moon have identical or very similar isotopic compositions for many elements, including tungsten. However, canonical models of the Moon-forming impact predict that the Moon should be made mostly of material from the impactor, Theia. Here we evaluate the probability of the Moon inheriting its Earth-like tungsten isotopes from Theia in the canonical giant impact scenario, using 242 N-body models of planetary accretion and tracking tungsten isotopic evolution, and find that this probability is, Tungsten isotopes between the Earth and Moon are compared in this new study. The authors find that traditional models of Moon formation are very unlikely to reproduce the Moon's Earth-like isotopic composition.

In der vorliegenden Arbeit wurde die terminologische Variation in den wichtigsten österreichischen Hochschulgesetzen und Rechtstexten zur Hochschulqualitätssicherung und deren jeweiligen englischen Fassung untersucht. Als Basis für die Untersuchungen diente eine Zusammenstellung von Begriffen und den dafür verwendeten englischen Übersetzungsmöglichkeiten, die aus einem speziell zusammengestellten Textkorpus extrahiert wurden. Zudem wurde aufgezeigt, wie in Zukunft sowohl bei der Erstellung der Ausgangstexte als auch bei der Übersetzung dieser in eine andere Sprache eine einheitlichere Terminologie erzielt werden kann. Dazu wurde auch mit den in die Erstellung der Texte und Übersetzungen involvierten Institutionen und Personen, insbesondere dem BMBWF und der AQ Austria sowie ihren Mitarbeiterinnen und Mitarbeitern, zusammengearbeitet. Ziel des Dissertationsprojektes war es, auf die inkonsistente Terminologieverwendung, die sowohl auf Textebene als auch textübergreifend zu beobachten ist, aufmerksam zu machen und konkrete Vorschläge für Gegenmaßnahmen zu machen. Ebenso wurde anhand der Informationen, die im Zuge der Auswertung der Forschungsergebnisse und der Interviews mit an der Hochschulrechtsübersetzung beteiligten Personen gewonnen werden konnten, der Versuch einer Beschreibung der Translationskultur im Bereich der Hochschulrechtsübersetzung gemacht., The thesis at hand researches terminological variation to be found in the most important Austrian laws and legal texts regulating the higher education system and its quality assurance as well as in their English translations. It is based on a comparison of German terms and their English equivalents found in a text corpus that was put together for the purpose of examining how often different variants for one term occur in the translations and whether there are comprehensible reasons for this phenomenon. Furthermore, possibilities are shown, how a more consistent terminology can be achieved in the source texts as well as in future translations. Therefore, a close contact was maintained with stakeholders involved in the creation and translation of the texts, in particular with experts from the Federal Ministry of Education, Science and Research as well as the Agency for Quality Assurance and Accreditation Austria. This research project aims at creating awareness for the inconsistent use of terminology that was found between the texts and including on a textual basis, and gives impulses for optimisation measures in connection with terminology management. The thesis also addresses the topic of translation culture, attempting at describing the translation culture in the field of legal translation in higher education and quality assurance. The description is based on information obtained in the course of the analysis of the research results, including interviews with different actors involved in this specific field.

Was kann man aus der Terminologie eines Gesetzes über Gemeinsamkeiten und Unterschiede zwischen verschiedenen Hochschulsystemen und Gesetzgebungen herauslesen? Mit dieser Frage beschäftigt sich die folgende Arbeit, die neben der Terminologie, auch auf das Thema der Qualitätssicherung ein großes Augenmerk legt. Dies wurde mit dem sektionsübergreifenden Hochschul-Qualitätssicherungsgesetz auch in Österreich zu einem festen Bestandteil der Organisationsagenden der verschiedenen Hochschuleinrichtungen und hat einige Änderungen für das österreichische Hochschulsystem mit sich gebracht. Anhand von ausgewählten Termini dieses Gesetzes und einiger weiterführenden Regelungen der AQ Austria werden die Hochschulsysteme Österreichs, Schwedens und Spaniens einander gegenübergestellt., What does the terminology of a law tell you about the similarities and differences of the tertiary education systems of different countries? That is one of the main topics discussed in this thesis. Particular attention is furthermore laid on quality assurance, which is a fixed agenda item in Austria’s higher education institutions since the Act on Quality Assurance in Higher Education was passed, and which has brought with it many changes to the higher education system. On the basis of handpicked terms, the Austrian higher education system is contrasted with the Swedish and Spanish systems.

Wustite, Fe1-xO, is an important component in the mineralogy of Earth's lower mantle and may also be a component of the core. Therefore its high pressure-temperature behavior, including its electronic structure, is essential to understanding the nature and evolution of Earth's deep interior. We performed X-ray diffraction and radiometric measurements on wustite in a laser-heated diamond anvil cell, finding an insulator-metal transition at high pressures and temperatures. Our data show a negative slope for this apparently isostructural phase boundary, which is characterized by a volume decrease and emissivity increase. The metallic phase of FeO is stable at conditions of the lower mantle and core, which has implications for the high P-T character of Fe-O bonds, magnetic field propagation, and lower mantle conductivity.